title: Radial to femoral arterial blood pressure differences in septic shock patients receiving high-dose norepinephrine therapy.
abstract: OBJECTIVE
  The accuracy of arterial blood pressure (ABP) monitoring is crucial in treating septic shock patients. Clinically significant differences in central to peripheral ABP could develop into sepsis during vasopressor therapy. The aim of this study was to investigate the difference between radial (peripheral) and femoral (central) ABP in septic shock patients receiving high-dose norepinephrine (NE) therapy.
  
  
  RESULTS
  This prospective observational study comparing simultaneous intra-arterial measurements of radial and femoral ABP was performed at a university-affiliated, tertiary referral center between October 2008 and March 2009. Patients with septic shock who needed continuous blood pressure monitoring and high-dose NE therapy 0.1 µg/kg per minute or greater to maintain mean arterial pressure (MAP) of 65 mmHg or greater were included. Statistical analysis was conducted using the Bland-Altman method for comparison of repeated measures. In total, 250 sets of systolic, mean, and diastolic femoral and radial ABP were recorded at baseline and after NE titration. Arterial blood pressure readings from the radial artery were underestimated compared with those from the femoral artery. Overall bias (mean difference between simultaneous measurements) between radial and femoral MAP was +4.9 mmHg; however, during high-dose NE therapy, the bias increased to +6.2 mmHg (95% limits of agreement: -6.0 to +18.3 mmHg). Clinically significant radial-femoral MAP differences (MAP ≥5 mmHg) occurred in up to 62.2% of patients with high-dose NE therapy.
  
  
  CONCLUSIONS
  Radial artery pressure frequently underestimates central pressure in septic shock patients receiving high-dose NE therapy. Femoral arterial pressure monitoring may be more appropriate when high-dose NE therapy is administered.
authors.affiliation: *Department of Emergency Medicine, Asan Medical Center; †Department of Anesthesiology and Critical Care Medicine, Hanyang University College of Medicine; and ‡Department of Pulmonary and Critical Care Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
authors.forename: Won Young
authors.initials: WY
authors.lastname: Kim
authors.forename: Jong Hun
authors.initials: JH
authors.lastname: Jun
authors.forename: Jin Won
authors.initials: JW
authors.lastname: Huh
authors.forename: Sang Bum
authors.initials: SB
authors.lastname: Hong
authors.forename: Chae-Man
authors.initials: CM
authors.lastname: Lim
authors.forename: Younsuck
authors.initials: Y
authors.lastname: Koh
mesh_terms: D000368:Aged; D062186:Arterial Pressure / Q000187:drug effects*; D001795:Blood Pressure Determination / Q000379:methods / Q000592:standards; D003422:Critical Care / Q000379:methods; D004305:Dose-Response Relationship, Drug; D005260:Female; D005263:Femoral Artery / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D011446:Prospective Studies; D017534:Radial Artery / Q000503:physiopathology*; D015203:Reproducibility of Results; D012772:Shock, Septic / Q000188:drug therapy* / Q000503:physiopathology; D014662:Vasoconstrictor Agents / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use
chemical_list: D014662:Vasoconstrictor Agents; D009638:Norepinephrine